This product highlight will discuss Stackpole's dual function components. Many applications require a parallel combination of varistor and capacitor. These two components protect the application against voltage surges (varistor) and against radio frequency noise (capacitor). Stackpole, through their strategic alliance with Keko Varicon, developed a single component that comprises both a varistor and a capacitor and therefore reduces the mounting space significantly. Two series of dual function components are available, the automotive OV series and the general purpose MV series. This product highlight will introduce each series and give applications for both of them.

OV and MV components are available in SMD and TH versions.

Automotive OV varicons

Safety and comfort are important features of modern automobiles. Among automotive applications, convenience applications represent their own field. Many electronic systems in vehicles make a drive safer and more comfortable. All these systems need a certain protection against voltage surges as well as a suppression of radio frequency noise. OV varistors / capacitors are an optimal solution for various wiper control systems and small DC motor drives for applications like side mirrors, sun roofs, side windows and doors. Stackpole offers standard and custom designed components for all automotive electronic systems. Customers can choose their own combination of electrical parameters, including capacitance, operating voltage and surge current. Operating voltage range for the OV series is 16Vdc to 56Vdc. Capacitance range is from 470nF to 4.7uF, load dump energy between 6J and 12J and rated peak single pulse transient current from 800A.

OV Component on a brush card for a wiper system DC motor

General purpose MV varicons

MV series varicons consist of a varistor in DC range from 3V to 125V (up to 170V upon request) and a capacitor in capacitance range from 10nF to 1uF in Z5U / Y5V dielectric. They can handle up to 2.5J of energy and are rated for up to 150 amps of current. These parameters can be adjusted to specific requirements as needed. The MV series is ideal protection of all sensitive electronic devices where overvoltage transients and high frequency noise produced by electromechanical devices (buzzers, relays, etc.) can occur.

Below are some examples of possible application circuits where MV varistors / capacitors can be used:

For more information about Stackpole products, contact Stackpole Electronics, Inc. at

Stackpole Electronics Inc. is a leading global manufacturer of resistors supplying to the worlds largest OEMs, contract manufacturers and distributors. Headquartered in Raleigh, N.C., the privately held company began manufacturing in 1928 as part of Stackpole Carbon Company in St. Mary's, Pennsylvania. Now part of the Akahane Stackpole Manufacturing Group (ASMG), Stackpole has manufacturing facilities in Japan, Taiwan, China and Mexico; warehousing facilities in El Paso, Shenzhen and Japan; and international sales offices in Tokyo, Taipei, London, Hong Kong and Shenzhen.

KEKO VARICON continues the tradition of ceramic electronic components started by Iskra Group 50 years ago. KEKO VARICON headquartered in Zuzemberk, Slovenia, has produced over-voltage protection devices for more than 15 years. Its name was derived from "VARistor" and "CONdensator", the old term for a capacitor. Today, KEKO VARICON is a leading supplier of over-voltage protection devices to many of the top electronics companies throughout the world. KEKO VARICON and SEI have formed a strategic alliance to jointly promote the sale of KEKO's products throughout North America.